HEMOGLOBIN AND HEMATOCRIT

20 G- 21 G

ROUTINE GAUGE OF NEEDLE

1-1.5 inches

Length of needle

18 G

Gauge of Pink Hub

21 G

Gauge of Green Hub

22 G

Gauge of Black Hub

23 G

Gauge of Blue (light/& turquoise) Hub

19, 20, 21, 22 G

Preferable gauge for adult

2

Maximum attempt of blood extraction

70% isopropyl alcohol

Recommended antiseptic to be used

SKIN PUNCTURE / DERMAL PUNCTURE

Puncture applicable to newborns

• To remove dead epidermal cells

• To facilitate free flow of blood

• To remove excess tissue fluid

Purpose of wiping first drop of blood in skin puncture

• Big toe

• Lateral heel

• Ring finger/middle finger

Areas used for skin puncture today

Lateral heel

medial or lateral portion of the plantar surface of the heel for <1 year old or infants

Earlobe

less pain, fewer free nerve endings, less tissue juice, not commonly performed today

Ring finger/middle finger

highly advisable puncture site (for skin puncture) for older children

less than 2mm

puncture depth for skin puncture

• altered blood composition

• decreased hematocrit due to tissue fluids

• hemolysis (bad results)

possible result of excessive squeezing

1. Easily accessible to the operator

2. Easy to manipulate

3. Less intimidating

4. Less equipment

Advantages of Skin Puncture

1. Less amount of blood is obtained

2. Additional and repeated tests

   cannot be done

3. Blood becomes easily hemolyzed

Disadvantages of Skin Puncture

(1) SYRINGE METHOD

(2) EVACUATED TUBE METHOD

Venipunture is also known as (1)__ & (2)___

Median cubital, cephalic, basilic

veins in the arms

veins in ventral forearm, wrist, back of hand, ankle, foot

alternate sites for venipuncture

15-30°

Angle of venipuncture

bevel up

BEVEL POSITION FOR VENIPUNCTURE

18-20”

length of tourniquet

3–4 inches (7.5–10 cm)

What is the recommended distance above the venipuncture site to apply a tourniquet?

40–60 mmHg

What is the recommended pressure when using a blood pressure cuff as a tourniquet for venipuncture?

Difficult to perform in infants, obese and burn patients

Disadvantages of Venipuncture

1. More volume of blood
2. Less painful
3. More options to site location
4. More dependable results; directly from circulation
5. Aliquots may be frozen for future use

Advantages of Venipuncture

15–30 minutes

How long should a coagulation tube be placed in an upright position at room temperature before storage at 4°C?

-20°C or lower

At what temperature should coagulation samples be stored if tests will be performed more than 48 hours after collection?

IMMEDIATE LOCAL COMPLICATION

– Localized hemoconcentration
– Syncope/fainting

Hematoma, Ecchymosis, Thrombosis, Thrombophlebitis

LOCAL DELAYED COMPLICATION

Hematoma

solid swelling of clotted blood w/in body’s tissue

Ecchymosis

discoloration of the skin resulting from the bleeding underneath typically caused by bruising

Thrombosis

occurs when blood clots block veins or arteries

Thrombophlebitis

swelling or inflammation of the vein caused by thrombus or blood clots

Serum hepatitis, AIDS

GENERAL LATE/ DELAYED COMPLICATION

EDTA, double oxalate, Sodium citrate, Heparin

ANTICOAGULANTS

EDTA

most routinely used anticoagulant in CBC

double oxalate

estimation of ESR by Wintrobe's method

Sodium citrate

coag studies; ESR by Westergren's method

Heparin

Osmotic Fragility Test (OFT), microhct capillary tubes

1.34ml of O2 and 3.47 mg of Fe2

1g of hgb is equals to?

brownish-yellow

When hemoglobin reacts with an acid (0.1 HCl), it is converted into acid hematin that is ____ in color

0.1 N HCl

Reagent of acid hematin

20 cmm or μl

blood measurement for acid hematin

Distilled Water

Dilluent for acid hematin

10 minutes at RT

Incubation time for Acid hematin

1. 2

2. Sahli Hellige hemometer

Place 0.1N HCl up to mark (1) ___ on the gram scale of a graduated (2)___.

20cmm

Draw blood sample, either capillary or venous, into a Sahli pipet up to mark ___

3x

Transfer blood sample into the hemometer tube containing the acid and rinse the pipette for at least (how many times)

10

Stand acid hematin for __ minutes at room temperature

1. comparator block

2. distilled water

Place the tube into the (1)____. Add (2)____ drop by drop until the color of the diluted sample matches that of the hemoglobin standard in the comparator block

directly

Read meniscus (directly or indirectly) on gram scale of the hemometer tuber

1. potassium ferricyanide

2. potassium cyanide

3. sodium bicarbonate

4. surfactant

4 Components of cyanmethemoglobin

Drabkin Reagent

Reagent of cyanmethemoglobin

0.02 mL

Blood measurement of cyanmethemoglobin

10 minutes at RT

Incubation time of cyanmethemoglobin

540nm

wavelength or absorbance of Cyanmethemoglobin

NOTE: directly proportional

1. ferrous

2. ferric

potassium ferricyanide in the reagent converts the hemoglobin iron from the (1)____ state to the (2)___ state to form methemoglobin

potassium cyanide

methemoglobin combines with ________ to form the stable pigment called cyanmethemoglobin

photometrically

The amount of cyanmethgb is measured

methemoglobin, Sulfhemoglobin, carboxyhemoglobin

ABNORMAL HEMOGLOBIN

centrifuge solution then measure the supernatant

Remedy for:

• Sensitivity of cyanmethemoglobin to light

• Turbidity due to high WBC and platelet count

add 0.01 ml of the patient’s plasma to 5 ml of the cyanmethemoglobin reagent.

Remedy for Lipemic samples

add 0.1 g of potassium carbonate to the cyanmethgb reagent/commercial reagent: KH2PO4 salt

Remedy for specimens of patients with abnormal globulins (MM)

MALE

HB, HCT & RBC LEVELS ARE HIGHER IN

HEMATOCRIT

measurement of the ratio of the volume occupied by the red blood cells (RBCs) to the volume of whole blood after centrifugation in a sample of capillary or venous blood expressed as a percentage

Blue

Color of plain capillary tube

Red

Color of heparnized capillary tube

5 mins at 10 000 rpm

Centrifuge time for capillary tube

two-thirds full.

Fill at least two capillary tubes approximately ____

• insufficient centrifugation

• Inclusion of the buffy coat from the measurement of the cell column height

• Improper use of the reader

• Fluid loss/ dehydration

FALSELY INCREASED

• Improper sealing of capillary tube

• Increased concentration of anticoagulant

• Overcentrifugation

• Improper use of the reader

• Blood loss (temporary effect) - plasma is replaced faster than erythrocytes

FALSELY DECREASED

45%-60%

Normal value of hct at birth

27%-44%

Normal value of hct at 1 y/o

40%-55%

Normal value of hct in men

36%-48%

Normal value of hct in women

Parallax error

some marker relative to something to be measured are subject to parallax error if marker is some distance away from object of measurement and not viewed from correct position

• Parallax error

• Centrifugation time

• Temperature

FACTORS AFFECTING HEMATOCRIT